Dr. Samuel McLean, an Emergency Medicine Physician, seeks a Mentored Patient-oriented Research Development Award from NIAMS. The project proposed for Dr. McLean's career development examines risk factors for the development of chronic pain after minor motor vehicle collision (MVC). Millions of patients are treated in US EDs after minor MVC each year, and chronic pain and disability after MVC (e.g. whiplash syndrome) result in tremendous societal costs. Despite this, few if any secondary prevention measures are available to prevent this outcome, largely because the pathophysiology of these disorders is poorly understood and limited data are available to identify those at highest risk. This project proposes to examine the ability of brief assessment measures collected in the ED to predict the development of chronic pain 6 months after the injury event. The proposed research plan includes a prospective longitudinal study of 720 patients presenting to the ED after MVC, and incorporates a brief ED assessment of both previously identified chronic pain risk factors, such as demographic and symptom characteristics, and previously understudied neurobiological factors, such as autonomic and hypothalamicpituitary- adrenal ("stress response system") function. Converging evidence, including pilot data collected, suggests that these neurobiological factors predict the development of both persistent pain and psychological sequelae after trauma. However, this has not been previously studied. Effectively identifying patients at high risk of developing chronic pain and gaining a better understanding of the pathophysiology of these sequelae are crucial to the development of successful secondary prevention interventions. Dr. McLean's career development activities build upon his previous experience coordinating ED-based studies and upon his 2 year partial institutional K12 award. His research activities take place in an ideal environment for mentorship and career development, and include 2 multi-disciplinary research centers: the Chronic Pain and Fatigue Research Center and the Trauma, Stress, and Anxiety Research Center. The goal of this research is to better understand why some individuals develop chronic pain after a traumatic event and others do not, and why pain and posttraumatic stress disorder symptoms often develop together. We hope to use this information to develop successful interventions to prevent these illnesses.